阔叶红松林恢复演替中功能性状和功能多样性对生态系统功能的影响机制

阔叶红松林是东北东部生产力和生物量最高、生物多样性最丰富的顶级森林群落，但目前红松原始林已所剩无几。本研究拟在前人工作基础之上，从功能性状和功能多样性的新视角，研究在阔叶红松林的恢复演替进程中生态系统功能变化的内在机制。在充分的前期研究的基础上，我们选择了关键的功能性状指标和生态系统功能参数，在研究功能性状、功能多样性和生态系统功能随着演替阶段的变化及其环境驱动力的同时，着重研究：1)生态系统功能是主要受功能多样性(多样性假说)还是优势种功能性状(生物量比例假说)的影响，抑或是由二者共同决定? 2)在不同的演替阶段，互补效应和抽样/选择效应对生态系统功能的相对作用大小有何差异?气候条件对这种差异有何种影响?研究不仅有助于解决生态系统功能的维持机制等关键理论问题，对于深入理解阔叶红松林恢复演替中不同尺度的生态过程和作用机制、为气候变化背景下科学的生态恢复实践提供理论依据也有重要的意义。

Broadleaf Korean pine forest (BKF) is not only the most productive and species-rich forest type in the east part of northeast China, but also the climatic climax in the region. However, most primary BKF has disappeared as a result of long-term human disturbance. The present study is designed to examine the changes of functional diversity and functional traits along a secondary succession gradient, and to explore the mechanisms that drive ecosystem-functioning changes during the ecological restoration process of BKF. We selected several critical ecosystem properties and key functional traits based on a number of previous studies and our own researches. In addition to examine the changes of functional traits, functional diversity and ecosystem functioning along the succession gradient and the environmental drivers of these changes, we focus on exploring two critical questions as follows. (1) Is ecosystem functioning mainly determined by functional diversity (the diversity-productivity hypothesis) or by the functional traits of dominant species (the biomass ratio hypothesis), or alternatively, controlled by the joint influences of them? (2) How dose the relative influence of complementarity effect vs. sampling (selection) effect on ecosystem functioning change along the secondary succession gradient? What is the role of climate in regulating these changes? Answering these questions is not only the basis to maintain the functioning and stability of ecosystems in a world undergoing rapid global changes, but also critical in understanding the mechanisms underlying the ecological restoration of BKF, which is in urgent need to improve the restoration and management technologies of the BKF ecosystem.